There are a few events that weekend as you mentioned. One of them that some of us participated in was a drive through Monterey and the 17 mile drive following the Concorso. It was pretty fun, and there was a barbecue afterward.
I will probably attend the historics as a freind of mine owns Colin Chapman's old Lotus and will race that weekend.
As far as staying there, since I live in the Bay Area, I will probably commute. But make reservations early if you plan to stay! The whole town books up pretty quickly.